In what environments can a dipolariton form? The article in Science in which it is introduced discusses it in the context of an optical cavity in a semiconductor. Can this quasiparticle occur elsewhere — as a free particle or on the surface or in the bulk of a metal, for example?

A dipolariton is a bosonic quasiparticle that consists of two excitons, one an electron together with a hole, the other an electron together with a photon. I'm asking this question to get a sense of whether a related question that was raised not too long ago makes sense.

EDIT: To be concrete, could a dipolariton form in the context of the system explored in this paper?